IEEE Trans Ultrason Ferroelectr Freq Control. 2016 Oct;63(10):1514-1524. doi: 10.1109/TUFFC.2016.2592688. Epub 2016 Jul 18.

Sparse SVD Method for High-Resolution Extraction of the Dispersion Curves of Ultrasonic Guided Waves.

IEEE transactions on ultrasonics, ferroelectrics, and frequency control

Kailiang Xu, Jean-Gabriel Minonzio, Dean Ta, Bo Hu, Weiqi Wang, Pascal Laugier

PMID: 27448347 DOI: 10.1109/TUFFC.2016.2592688

Abstract

The 2-D Fourier transform analysis of multichannel signals is a straightforward method to extract the dispersion curves of guided modes. Basically, the time signals recorded at several positions along the waveguide are converted to the wavenumber-frequency space, so that the dispersion curves (i.e., the frequency-dependent wavenumbers) of the guided modes can be extracted by detecting peaks of energy trajectories. In order to improve the dispersion curve extraction of low-amplitude modes propagating in a cortical bone, a multiemitter and multireceiver transducer array has been developed together with an effective singular vector decomposition (SVD)-based signal processing method. However, in practice, the limited number of positions where these signals are recorded results in a much lower resolution in the wavenumber axis than in the frequency axis. This prevents a clear identification of overlapping dispersion curves. In this paper, a sparse SVD (S-SVD) method, which combines the signal-to-noise ratio improvement of the SVD-based approach with the high wavenumber resolution advantage of the sparse optimization, is presented to overcome the above-mentioned limitation. Different penalty constraints, i.e., l

Publication Types

• Journal Article
• Research Support, Non-U.S. Gov't